Heel molding method



Sept. 1932- J. o. GOODWIN 1,877,298

HEEL MOLDING METHOD Filed Oct. 7. 1929 Z4 F194} 22 a 20 2 1/ 25 I K 2] gwuemto-z 1/ F 5 Jafilz 0' 600070112,

Patented Sept. 13, 1932 tom-res eras as earsNr D P-ms ress-1v o. eoonwnv, or AKRON, onro, A$SIGNOR T SEIBERLING/RUBBER] COMPANY, as}

BARBERTQN, OHIO,'A CORPORATION OF DELA ARE.

HEEL MOLDING MnrHon This invention relates'to the manufacture.

Such heels'have many advantages over those employing-embedded metal washers or other rigid nail-retaining means, but their manufacture is attended With, diificulties V la'rgely due to the tendency of the mailing insert to become displaced in theheel body during molding and during the charging of the molds vvithbodyrubber when performed by a mold-filling machine.

- The object of my invention is to over- 1 come, in an improved manner, the difliculties encountered in making heels of the type re ferred to. This application covers the method disclosed in my prior application Ser. No.

asaooza, filed April 18, 1929, together with 29 additional matter, and is a continuation in part of said application. U Of the accompanying drawing: 7

face of one form of heel i5 present invention.

Fig. 2 is a longitudinal'section of the heel on the line 22 of Fig. 1. l 7

Fig.3 is across section onthe line 3ao- FIZFi-g; 1. I l

0' Fig. 4 is a partial longitudinal section showing the heel mold in the course of being 1 charged With body rubber in a mold-filling machine. p 5 18 a 33 showing the mold closed upon the heel.

Contrary to the 1 usual practice With the Washer-insert and some other types of heels, the heel in this case is molded and vulcanized ,-;wi,th its attaching face down in the mold,

cavity, and the floor ofsaid cavityjisfshaped to' form said attaching face, the latter preferably being more or less concave. InTfollowing this practice heretofore, it, has re- 'cently been proposed to anchorthe nailing insert against displacement in the plane of.

Fig'zl is a plan view showing the attaching produced by the;

' of the heel.

Application filed october 7, 1929. Serial No. 397,900.

sults in securin the insert as a Whole against displacement, it still permits some flowing of the outer edges thereof during vulcanization,and that portion of the insert adjacent i the breast edge may become more'or less displaced When the rubber pressure is exerted toward that'edge by running the mold cavities through a filling machine rear end fore-.

most which has been found to be the. best practice. Furthermore, when the insertis 'placed on the bossias heretofore arranged, a

tendency of said insert to rise or curl up at.

the outer edges has been observed.

My present invention includes certain steps and devices for externally anchoring assume a non-flat condition, Which steps and devices may, if desired, supplement and co- I the insert, especially at the breast edge, and for counteracting its tendency to curl up. or f Referring to the draWing,,1O is a. vul V canized, soft-rubber heelbody, and 11 is a nail-head retaininglayer or insertembedded inand forming part of the attaching face- Said attaching face is prefers ably slightly dished or concave and provided around its side and rear edges With a beveled or upwardly inclined edge lip 12 on the 7 sure against the shoe bottomg The layer 11 cushion body 10 to forma tight edge clomay be of any suitable composition preferenable it to be integrally vulcanized tof' the ably v including soft rubber to ren er said i 7 layer flexible and more or less resilient, and partial longitudinal section ,rubber cushionbody' 10. The rubber of this, layer may be stiflened Withan intermixture 1 of a suitable organic, fibrous material such,

for example, as animal hair.

and parallel respectively to the outer side and rear edges 15,15 and the forward or breast edge 16 of the heel, the-two forward.

corner recesses 14 being L-shaped. 'Of these recesses, the ones .14, 14 adjacent the breast edgesarethe more important and the others may in some cases be omitted. Thenumber, i

-. material, flush with the upper face of layer 11 and integrally uniting the edges of said 1 layer with the side marginal portions of the rubber body 10. The breast recesses 14, is are separated by similar bridgesj18. The several recesses collectively occupy the maj or portion of the corresponding edges of the attachinglayer along which theyextendthis featureb'eing more important at thebreast edge for the reason stated.

11 have further shown a D-shaped recess 19 in the central region of the attaching layer" ll, with'its edges parallel to the outline of the heehand surrounded by the nailing zone, said recess preferably extending clear through or perforating the layer 11', and being formed in the blank for said layer, which isfcut in annular, heel-shaped form before placing in the'mold. In the center of the recess '19 is'a supporting stud or column 20 forming part of the rubber cushion body 10, for a purpose hereinafter described.

The several recesses in theattaohing face of the heel are'formed by, or mate with, complemental projections formed onthe mold.

21 is the body plate of themold, formed with I molding cavities 22, and 23 is the top or cover 'plate,'the I under side of the latter being shaped over the mold cavities to form the tread faces of the heels, which maybe approximately flat as shown and provided with the usual raised, non-slip and/or brand markings;

'The bottom wall or floor of each mold cavi ty is shaped to form the attaching face of the heel including the flexible marginal lip 12,and

" :is shown as provided with a central, upward 'lyprojecting, annular boss 2 corresponding 7 to the large central recess 19 in the heel, and

withupwardly-projecting ribs 25, 26 of less height than theboss, for forming the rear recess 13 ,and the breast recess 14:, respect1vely,i'n the'heel, other s1m1lar ribs being I provided'for fornnng the other marginal re- The, height of the boss 24 is made greater thanthe thickness ofthe nailing insert 11, so

' that when said insert is placed on said boss and supportedon thefloorof the mold cavity it will tend to lie fiat and not curl up or rise at its outer edges, the frictional hold of the ribs such as 25, 26 on these outeredg'es further tending to hold the insert flat. Since a" boss of this height rather deeply indents the heel body, I prefer to centrally recessthe boss 24 to formthe rubber stud or column 20 for supporting the central tread wall of the heel,

although modified expedients could be adopt ed and this supporting member might be omitted. o p 7 In the molding of the heel under vulvanizing heat and pressure, the mold ribs such as 25 and 26 externally anchor the nailing insert 11 and prevent it from displacement orflowing to the edges of the body rubber and producing defective heels. These ribs, or one or more-of them for forming one or more of therecesses 18, 133,141, llfiin the seating face of the heel, and especially the-rib or ribs at the breast edge, could be employed as the sole expedient for anchoring the insert 11 against 'displacement"and'flowing, and the boss 24:

with its corresponding heel recess 19 could be omitted. However, I prefer, especially with the softer stocks, to provideone or more o entral mold bosses such as 24,- eith-er sol1d,o1",

annular asshown, or of other form, fora'lso 1 internally anchoring the insert, in which case I r the boss and ribs supplement each other and mutually relieve each other of apart of the;

anchoring'duty. it will also be understood, that the function ofthe deep boss 24 in caus-j ing the insert to lie flat could be employed apart from the external anchoring ribs.

The marginal mold ribs, or either of them,

and said ribs or eitherof themin conjunction r i with the mold boss 24, together with the operations performed thereby,-are useful notonly in preventing flow and displacement of thenailing insert due to molding pressureand j heat, butalso in avoiding displacement due i to pressure of the body stock during filling of the mold in a machine. liig. 4 represents a portion of such a machine including an upper or nozzle plate 27 and a lower bed plate 28,

between-which the moldplate 21 is-forced rightward, in the direction of the arrow, by a suitable pusher. 29 is a funnel-shapednozzle chamber and 30 is plastic rubber'composition' adapted to be forced therethrough'by suitable means and extruded through the narrow out- 11.0

let slot of the nozzle into the mold cavities 22, said slot extending transversely for "the full width of the mold. Thereby the nailing; insert 11 is progressively embedded in] the plastic body-rubber, composition, beginning" at the rear endof the-heelanden ding at the,

breast end, since the mold plate is pushed through with its cavities rear-end foremost so that the pressure of the rubber willjbej mostly in the direction ofthe breast edge and any occasional imperfectionscaused by dis-f placement or overflow of theinsert will occur at the breast edge where they will be least.

conspicuous when the heel is applied to a shoe,

Obviously the rib or ribs suchas 26' which" are located adjacent the breast edge are most effective in preventing suchdisplacement in; I

the filling operation as thuscarried out.

After the mold has been filled,- its covers plate 23 is applied, the, mold is placedin a I heater press and the heels vulcanized the usual manner, the vulcanization resulting in an integral union between the heel components.

While a preferred embodiment has been described, there is opportunity for considerable variation in the method and apparatus as here disclosed, without departing from my invention as defined in the claims, and I do not wish to be limited except as thus defined.

I claim: i

1. The method of making rubber heels which comprises inserting a plastic attaching layer in the top side of a cushion rubber heel body, confining said layer within the margin of the heel, along an outer edge of said layer, during its insertion in the body rubber, sufficiently to prevent flow thereof to the adj acent outer edge face of the heel, and vulcanizing the heel under heat and molding pressure.

2. The method of making rubber heels" which comprises inserting a plastic attaching layer in the top side of a cushion rubber heel body, externally confining said layer within the margin of the heel along the breast edge of said layer for the greater part of its length during the insertion of said layer in the body rubber to prevent flow of said layer to the adjacent breast edge of the heel, and vulcanizing the heel under heat and molding pressure.

3. The method of making rubber heels which comprises inserting aplastic'attaching layer in the top side of a cushion rubber heel body, externally confining said layer within the margins of the heel along the side edges and breast edge of said layer for the greater part of the length of said edges during the insertion of said layer in the body rubber to prevent flow of said layer to the adjacent edge faces of the heel, and vulcanizing the heel under heat and molding pressure.

4. The method of making rubber heels which comprises inserting a plastic attaching layer in the top side of a cushion rubber heel body, confining said layer both internally arid externally within the margins of the heel, during. the insertion of said layer in the body rubber, and vulcanizing theheel under heat and molding pressure. v

5. The method of making rubber heels which comprises inserting, in the top side of a cushion rubber heel body, a perforated plastic blank for attaching layer, confining said layer by the edges of its perforation and also by an outer edge, within the margin of the heel, during the insertion of said layer in the body rubber, and vulcanizing the heel under heat and molding pressure.

6. The method of making rubber heels which comprises inserting, in the top side of a cushion rubber heel body, a centrally recessed blank for an attaching layer, confining said layer by the edges of its central recess, and also along its breast edge for the greater part of the length of said edge, during the insertion of said layer in the body rubber, and vulcanizing the heel under heat and molding pressure.

7 The method of making rubber heels whichcomprises anchoring a nailing insert by an outer edge thereof at the bottom of amold cavity, progressively embedding said insert by extruding plastic rubber composition into said mold'cavity while the insert is so anchored, and vulcanizing the heel in said cavity.

8. The method of making rubber heels" which comprises externally anchoring a nailing insert by its breast edge in a mold cavity, and progressively extruding plastic rubber into said cavity, from the rear to the breast end, while the insert is so anchored to embed said insert. i

9. The method of making rubber heels which comprises anchoring a perforated nailing insert by its internal and external edges in a'mold cavity, and progressively extruding plastic rubber composition into said cavity to embed anchored.

10.,The method of making rubber heels whichgcomprises anchoring; a perforated, flexible, non-metallic nailing member at the bottom of a mold cavity by means of a prothe insert, while the latter is so 1 insert and progressively embedding said insert by extruding plastic rubber composition into sald cavity while the insertis so anchored.

In witness whereof I have hereuntosetmy hand this 2nd day of October, 1929.

J O. GOODWIN. 

